The described invention relates in general to a glue or adhesive formulation, and more specifically to a two-part polyurethane, pourable glue formulation. Some commercially available glue products such as glue sticks typically include PVP (polyvinylpyrrolidone) or modified-PVOH (polyvinyl alcohol) polymers. These polymers provide such glue products with the strength required to adhere paper items to one another, but lack the adhesive capacity to join other more difficult materials such as wood, metal and plastic. With regard to pourable glue products, current water-based wood glues utilize PVAc (polyvinyl acetate) for adhering wood substrates to one another. When adhesion is required for non-wood substrates, either a two-part epoxy or a one-part polyurethane adhesive is typically used.
Waterborne urethane polymers are sometimes used as a base for products such as waterproof stains or clear shellacs. However, these polymers are not typically used for arts and crafts applications despite the fact that polyurethanes have a greater range of adhesion than many of the polymers used to formulate the glues and adhesives discussed above. Therefore, there is an ongoing need for a high-strength glue formulation for joining wood, metal and plastic, wherein the glue formulation includes waterborne polyurethanes.